JP2585033B2 - Pneumatic drive - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to an improvement in a pneumatic drive device having a positioning function applied to a lift valve such as a needle valve.

(Prior Art) Conventionally, as this type of pneumatic drive device, for example,
FIG. 4 and FIG. 4 are known.

The pneumatic drive device 100 is basically a hollow main body 1
01 and the supply / discharge chamber 10 provided on the main body 101 from above the main body 101
2, a discharge chamber 103, a control pressure chamber 104, a drive pressure chamber 105, a discharge diaphragm 106, control diaphragms 107 and 108, a drive diaphragm 109, a discharge seat 106 connecting the discharge diaphragm 106 and the control diaphragms 107 and 108, and a main body 101. A supply path 111 provided to guide the driving air from the supply source to the supply / discharge chamber 102, a supply path 112 provided to the main body 101 to guide the driving air of the supply / discharge chamber 102 to the driving pressure chamber 105, and a valve. A discharge path 113 provided in the seat body 110 for guiding the driving air of the supply / discharge chamber 102 to the discharge chamber 103; an open path 114 provided in the main body 101 for guiding the driving air of the discharge chamber 103 to the atmosphere; Provided in the supply and discharge chamber
A discharge path 115 for guiding the driving air of 102 to the atmosphere, a control path 116 provided in the main body 101 for guiding the control air from the supply source to the control pressure chamber 104, and an upwardly directed upward path provided in the middle of the supply path 111. A valve seat 117 and an upwardly directed lower valve seat 11 provided in the middle of the discharge passage 113.
8, a valve element 119 provided on the main body 101 so as to be able to move up and down and abutting on the upper valve seat 117 and the lower valve seat 118, and connected to a valve rod (not shown) of the lift valve provided on the drive diaphragm 109. Drive rod 120, a valve body spring 121 provided on the main body 101 to lower the pressure of the valve body 119, and a valve seat body 110 provided on the main body 101.
Zero-adjust spring 122 to lower the pressure, and valve seat body 110
A range spring 123 interposed between the drive rod 120 and the drive rod 120 to increase the pressure of the valve seat body 110, and a return spring 124 provided to the main body 101 to increase the pressure of the drive rod 120.

Thus, this is because the driving air from the source (1.
4 or 2.4 kgf / cm ² ) is supplied to the supply path 111, and control air (0.2 to 1.0 kgf / cm ² ) from a supply source is supplied to the control path 116, and the control diaphragms 107 and 108 having a pressure receiving area difference.
, And the resultant force of the upper power of the range spring 123 and the lower pressure of the zero-adjust spring 12 balance the drive diaphragm 109 at a predetermined position.

From such a state, if the pressure of the control air is increased,
The valve seat 1 is controlled by the control diaphragms 107 and 108 by the increment.
10 and the valve body 119 move upward, the space between the valve body 119 and the upper valve seat 117 opens,
The driving air from the supply path 111 is supplied between the valve element 119 and the upper valve seat 117 → the supply / discharge chamber 102 → the supply path 112 → the driving pressure chamber 105, and the driving diaphragm 109 moves downward against the return spring 124. .

When the driving diaphragm 109 moves downward, the elasticity of the range spring 123 decreases, and the valve seat 110 and the valve 119
Is moved downward, the space between the valve element 119 and the upper valve seat 117 is closed, the driving air from the supply path 111 is not supplied to the driving pressure chamber 105, and the driving diaphragm 109 is maintained at the lower position.

Conversely, when the pressure of the control air is reduced, only the valve seat body 110 is moved downward by the control diaphragms 107 and 108 by the reduced amount, and the space between the valve body 119 and the lower valve seat 118 is opened. Is discharged to the atmosphere through the feed path 112 → the supply / discharge chamber 102 → between the valve element 119 and the lower valve seat 118 → the discharge path 113 → the discharge chamber 103 → the open path 114, and the drive diaphragm 109 depends on the elasticity of the return spring 124. To rise.

When the driving diaphragm 109 moves upward, the elasticity of the range spring 123 increases, and the valve seat body 110 moves upward by that amount,
The space between the valve element 119 and the lower valve seat 118 is closed, and the driving air in the driving pressure chamber 105 is not exhausted to the atmosphere, and the driving diaphragm 109 is kept at the position moved upward.

By the way, in such a device, when the drive diaphragm 109 is maintained at a predetermined position, the upper valve seat 117 and the valve element 119 are slightly separated from each other, and a part of the drive air from the supply path 111 is intentionally removed. Between the upper valve seat 117 and the valve element 119 → the supply / discharge chamber 102 → the discharge path 115, and is constantly discharged to the atmosphere and consumed.

However, such an arrangement has a drawback that if the consumption is not equal to or more than a certain value, the ascending and descending stroke of the driving diaphragm 109 is not stable and the operation is slow, so that the consumption of the driving air is large.

(Problems to be Solved by the Invention) In view of the above-mentioned problems, the present invention has been made in order to solve the above problems, and its object is to reduce the consumption of driving air. To provide a pneumatic drive device.

(Means for Solving the Problems) A pneumatic drive device according to the present invention includes a hollow main body, a valve seat body provided so as to be able to ascend and descend above the main body and forming a supply / discharge chamber with the main body, A control diaphragm provided on the main body and connected to the valve seat body to form a discharge chamber with the main body and the valve seat body; a partition wall provided on the main body to form a control pressure chamber with the main body and the control diaphragm; A drive diaphragm provided to form a drive pressure chamber with the main body and the partition wall, and a supply path provided in the main body and guiding drive air from a supply source to a supply / discharge chamber,
A supply path provided in the main body for guiding the drive air of the supply / discharge chamber to the drive pressure chamber; a discharge path provided in the valve seat for guiding the drive air of the supply / discharge chamber to the discharge chamber; and a discharge path provided in the main body. An open path for guiding the drive air of the discharge chamber to the atmosphere, a control path provided in the main body for guiding the control air from the supply source to the control pressure chamber, and an upward valve seat provided in the middle of the supply path. , An upwardly-facing lower valve seat provided in the middle of the discharge path, a valve body provided on the main body so as to be able to ascend and descend and seating on the upper valve seat and the lower valve seat, and a drive diaphragm side which is provided through a partition wall so as to be able to ascend and descend. An interlocking rod connected to the
A drive rod provided on the drive diaphragm and connected to the valve stem of the elevating valve, a valve body spring provided on the main body for lowering the valve body, and a zero-adjust spring provided on the main body for lowering the valve seat body A range spring interposed between the valve seat and the interlocking rod to increase the pressure of the valve seat, a return spring provided on the main body to increase the pressure of the drive rod, and a supply source provided on the valve or the main body. It is characterized by the fact that it is composed of pores that directly guide the driving air from the air supply and discharge chambers.

(Operation) When the driving diaphragm is maintained at a predetermined position, the driving air from the supply source is directly guided to the supply / discharge chamber through the pores, and the same amount of driving air is supplied between the lower valve seat and the valve body. Is guided to the discharge chamber through the gap.

At this time, since there is no pressure difference before and after the pores that determine the amount of driving air passing, consumption of driving air from the supply source to the atmosphere is reduced.

(Example) Hereinafter, an example of the present invention will be described with reference to the drawings.

FIG. 1 is a vertical sectional front view showing a pneumatic drive device according to an embodiment of the present invention. FIG. 2 is a vertical sectional side view showing only a main part.

The pneumatic driving device 1 includes a main body 2, a valve seat 3, a control diaphragm 4, a partition wall 5, a driving diaphragm 6, a supply path 7, a supply path 8, a discharge path 9, an open path 10, a control unit 11, a control valve 11, and an upper valve. The main part is composed of seat 12, lower valve seat 13, valve body 14, interlocking rod 15, drive rod 16, valve body spring 17, zero adjust spring 18, range spring 19, return spring 20, and fine hole 21. ing.

 The main body 2 is hollow.

In this example, the upper wall 22, the lower wall 23, the peripheral wall 24, and the upper wall 22
And a cylinder 25 which is vertically mounted on the cylinder.

The valve seat body 3 is provided so as to be able to move up and down inside the main body 2, and forms a supply / discharge chamber 26 with the main body 2.

In this example, a piston 27 that is loosely fitted in the lower half of the cylinder 25 so as to be able to move up and down, and a control rod that abuts these lower ends.
28, a supply / discharge chamber 26 is formed in the upper half inside the piston 25.

The control diaphragm 4 is provided on the main body 2 and is provided with the valve seat body 3.
And a discharge chamber 29 is formed by the main body 2 and the valve seat body 3.

In this example, it consists of one thing provided on the peripheral wall 24 so as to have a pressure receiving area, which is connected to the control rod 28.

A discharge chamber 29 is formed in a portion surrounded by the peripheral wall 24, the cylinder 25, the piston 27, the control rod 28, and the diaphragm 30 attached to the peripheral wall 24 and the control rod 28.

The partition wall 5 is provided on the main body 2 and forms a control pressure chamber 31 by the main body 2 and the control diaphragm 4.

In this example, a control pressure chamber 31 is provided on the peripheral wall 24 and is surrounded by the peripheral wall 24, the control diaphragm 4, and the partition wall 5.

The driving diaphragm 6 is provided on the main body 2 and forms a driving pressure chamber 32 by the main body 2 and the partition wall 5.

In this example, a drive pressure chamber 32 is formed in a portion provided on the peripheral wall 24 and surrounded by the peripheral wall 24, the partition wall 5, and the drive diaphragm 6.

The supply path 7 is provided in the main body 2 and guides driving air from a supply source to the supply / discharge chamber 26.

In this example, it is provided on the peripheral wall 24, a driving air supply source (not shown) is connected to the outer end, and a filter 33 is provided in the middle.

The supply path 8 is provided in the main body 2 and guides the driving air of the supply / discharge chamber 26 to the driving pressure chamber 32.

 In this example, it is provided on the peripheral wall 24.

The discharge furnace 9 is provided in the valve seat body 3 and guides the driving air for the supply and discharge 26 to the discharge chamber 29.

In this example, they are provided at the center of the piston 27 and above the control rod 28, respectively.

The open path 10 is provided in the main body 2 and guides the driving air of the discharge chamber 29 to the atmosphere.

In this example, it is provided on the peripheral wall 24, and a filter 34 is provided at the outer end and is open to the atmosphere.

The control path 11 is provided in the main body 2 and guides control air from a supply source to the control pressure chamber 31.

In this example, it is provided on the peripheral wall 24, and a control air supply source (not shown) is connected to the outer end.

The upper valve seat 12 is provided upward in the middle of the supply path 7.

 In this example, it is formed on the upper surface of the cylinder 25.

The lower valve seat 13 is provided upward in the middle of the discharge passage 9.

 In this example, it is formed on the upper surface of the piston 27.

The valve element 14 is provided on the main body 2 so as to be able to move up and down, and rests on the upper valve seat 12 and the lower valve seat 13.

In this example, a part of the supply path 7 and the supply / discharge chamber 26 are inserted and provided so as to be able to move up and down with respect to the peripheral wall 24 and the cylinder 25. It has a spool shape with a valve seat.

The interlocking rod 15 is provided to penetrate the partition wall 5 so as to be able to move up and down, and is connected to the drive diaphragm 6 side.

In this example, the lower end of the drive rod 16 is in contact with the upper end of the drive rod 16 so as to be able to move up and down, seal, and penetrate the partition wall 5.

The drive rod 16 is provided on the drive diaphragm 6 and is connected to the valve stem of the elevating valve.

In this example, the lower wall 23 is provided so as to be able to move up and down, and the upper end is sealed and attached through the drive diaphragm 6, and the lower end is a valve stem (shown in the figure) of an elevating valve such as a needle valve. )).

The valve body spring 17 is provided on the main body 2 to lower the pressure of the valve body 14.

 In this example, it is interposed between the upper wall 22 and the valve body 14.

The zero adjust spring 18 is provided on the main body 2 and lowers the pressure of the valve seat body 3.

In this example, the spring holder 35 is interposed between the valve holder 3 and the spring holder 35 that is fitted to the cylinder 25 so as to be able to move up and down.
The spring force can be adjusted by moving the 35 up and down.

The range spring 19 is interposed between the valve seat 3 and the interlocking rod 15 to press the valve seat 3 upward.

The return spring 20 is provided on the main body 2 and presses the drive rod 16 upward.

In this example, it is interposed between the lower wall 23 and the drive rod 16.

The fine holes 21 are provided in the valve body 14 or the main body 2 and guide the driving air from the supply source directly to the supply / discharge chamber 26.

 In this example, it is provided on the valve element 14.

 Next, the operation will be described based on such a configuration.

The driving air (1.4 or 2.4 kgf / cm ² ) from the supply source is supplied to the supply path 7 and the control air (0.
^{2 to} 1.0 kgf / cm ² ) is supplied to the control path 11.

When the control air is supplied from the control passage 11 to the control pressure chamber 31, the resultant force of the upper power by the control diaphragm 4 and the upper pressure of the range spring 19 and the zero-adjust spring 18
The driving diaphragm 6 is maintained at a predetermined position by balancing the lower pressure.

From such a state, if the pressure of the control air is increased,
The valve seat 3 and the valve body 14 are moved upward by the control diaphragm 4 by the increased amount, the space between the valve body 14 and the upper valve seat 12 is opened, and the driving air from the supply path 7 is supplied to the valve body 14 and the upper valve seat 12. The space is supplied to the supply / discharge chamber 26 → the supply path 8 → the drive pressure chamber 32, and the drive diaphragm 6 moves downward against the return spring 20.

When the driving diaphragm 6 moves down, the range spring
The elasticity of the valve 19 is reduced, the valve seat 3 and the valve 14 are moved downward by that amount, the space between the valve 14 and the upper valve seat 12 is closed, and the driving air from the supply passage 7 is supplied to the driving pressure chamber 32. Instead, the driving diaphragm 6 is kept at the lower position.

Conversely, when the pressure of the control air is reduced, only the valve seat body 3 is moved downward by the control diaphragm 4 by the reduced amount, and the space between the valve body 14 and the lower valve seat 13 is opened. Is discharged to the atmosphere through the feed path 8 → the supply / discharge chamber 26 → between the valve element 14 and the lower valve seat 13 → the discharge path 9 → the discharge chamber 29 → the open path 10; the driving diaphragm 6 depends on the elasticity of the return spring 20. Move up.

When the driving diaphragm 6 moves upward, the range spring
The elasticity of 19 increases, and the valve seat 3 moves up by that much, and the valve
The space between the lower valve seat 13 and the lower valve seat 13 is closed, and the driving air in the driving pressure chamber 32 is not exhausted to the atmosphere, and the driving diaphragm 6 is kept at the upper position.

Thus, when the driving diaphragm 6 is maintained at a predetermined position, the driving air from the supply source is directly supplied to the supply / discharge chamber through the fine holes 21.
26, and an equal amount of driving air is supplied to the valve element 14.
The liquid is guided to the discharge chamber 29 through the discharge path 9 from the gap between the valve seat 13 and the lower valve seat 13.

At this time, since the pressure difference between the supply path 7 and the supply / discharge chamber 26 is reduced, the amount of driving air consumed from the supply source to the atmosphere is reduced.

In the above embodiment, the main body 2 is divided into a plurality of parts and is united. However, the way of division may be determined as appropriate.

Although the valve seat 3 is constituted by the piston 27 and the control rod 28 in the above embodiment, the present invention is not limited to this. For example, these may be integrally formed.

Although the pores 21 are provided in the valve body 14 in the above embodiment, the present invention is not limited to this. For example, the pores 21 may be provided in the main body 2.

Although the discharge chamber 29 is formed by providing the diaphragm 30 in the above embodiment, the present invention is not limited to this. For example, the discharge chamber 29 may be omitted and formed directly by the control diaphragm 4.

(Effects of the Invention) As described above, according to the present invention, the following excellent effects can be obtained.

(1) Main body, valve seat, control diaphragm, partition wall, drive diaphragm, supply path, feed path, discharge path, open path, control path, upper valve seat, lower valve seat, valve body, interlocking rod, driving rod , Valve body spring, zero-adjust spring, range spring, return spring, and pore,
In particular, since the fine holes are provided between the supply path and the supply / discharge chamber, the consumption of driving air can be reduced.

(2) In particular, since only the pores are provided, the structure is simple and the cost is not excessive.

[Brief description of the drawings]

FIG. 1 is a vertical sectional front view showing a pneumatic drive device according to an embodiment of the present invention. FIG. 2 is a vertical sectional side view showing only a main part. FIG. 3 is a longitudinal sectional front view showing a conventional pneumatic drive device. FIG. 4 is a vertical sectional side view showing only a main part. DESCRIPTION OF SYMBOLS 1 ... Pneumatic drive device 2 ... Main body 3 ... Valve seat body 4 ... Control diaphragm 5 ... Partition wall 6 ... Drive diaphragm 7 ... Supply path 8 ... Feeding path 9 ... Discharge path 10 ... … Open path 11… Control path 12 …… Upper valve seat 13 …… Lower valve seat 14 …… Valve 15 …… Interlocking rod 16 …… Drive rod 17 …… Valve spring 18 …… Zero-adjust spring 19… … Range spring 20 …… Return spring 21 …… Pore

Claims (1)

(57) [Claims] A valve body provided in the main body so as to be capable of ascending and descending to form a supply / discharge chamber; and a main body and a valve provided in the main body and connected to the valve seat body. A control diaphragm that forms a discharge chamber with the seat body, a partition wall that is provided on the main body and forms a control pressure chamber with the main body and the control diaphragm, and a drive pressure chamber that is provided on the main body and that is formed by the main body and the partition wall A driving diaphragm, a supply path provided in the main body and guiding the driving air from the supply source to the supply and discharge chamber, and a supply path provided in the main body and guiding the driving air of the supply and discharge chamber to the driving pressure chamber,
A discharge passage provided in the valve seat body to guide the driving air of the supply / discharge chamber to the discharge chamber, an open passage provided in the main body to guide the driving air of the discharge chamber to the atmosphere, and a supply source provided in the main body from the supply source. A control path for guiding the control air to the control pressure chamber, an upward valve seat provided in the middle of the supply path, an upward valve valve seat provided in the middle of the discharge path, and provided in the main body so as to be able to move up and down. A valve body that rests on the upper valve seat and the lower valve seat, an interlocking rod penetrating the partition wall so as to be able to move up and down and connected to the drive diaphragm side, and is connected to the valve rod of the lift valve provided on the drive diaphragm. Drive rod, a valve body spring provided in the main body to lower the valve body, a zero adjust spring provided in the main body to lower the valve seat body, and interposed between the valve seat body and the interlocking rod. Range spring that presses the valve seat upward, and raises the drive rod provided on the body. Pneumatic drive device comprising a return spring, a guide budge pores drive air directly supply discharge chamber from the supply source provided in the valve body or body, that consisted of.